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<FONT color="green">001</FONT>    package edu.hawaii.duedates;<a name="line.1"></a>
<FONT color="green">002</FONT>    <a name="line.2"></a>
<FONT color="green">003</FONT>    import java.io.File;<a name="line.3"></a>
<FONT color="green">004</FONT>    import java.io.FileNotFoundException;<a name="line.4"></a>
<FONT color="green">005</FONT>    import java.io.FileOutputStream;<a name="line.5"></a>
<FONT color="green">006</FONT>    import java.io.IOException;<a name="line.6"></a>
<FONT color="green">007</FONT>    import java.io.PrintStream;<a name="line.7"></a>
<FONT color="green">008</FONT>    import java.util.ArrayList;<a name="line.8"></a>
<FONT color="green">009</FONT>    import java.util.List;<a name="line.9"></a>
<FONT color="green">010</FONT>    <a name="line.10"></a>
<FONT color="green">011</FONT>    /**<a name="line.11"></a>
<FONT color="green">012</FONT>     * ErrorLogger logs the error stack and determines whether which output is<a name="line.12"></a>
<FONT color="green">013</FONT>     * most appropriate for a developer or ordinary user.<a name="line.13"></a>
<FONT color="green">014</FONT>     * <a name="line.14"></a>
<FONT color="green">015</FONT>     * @author Anthony M. Du<a name="line.15"></a>
<FONT color="green">016</FONT>     */<a name="line.16"></a>
<FONT color="green">017</FONT>    <a name="line.17"></a>
<FONT color="green">018</FONT>    public class ErrorLogger {<a name="line.18"></a>
<FONT color="green">019</FONT>    <a name="line.19"></a>
<FONT color="green">020</FONT>      // List for command line arguments.<a name="line.20"></a>
<FONT color="green">021</FONT>      private final List&lt;String&gt; args = new ArrayList&lt;String&gt;();<a name="line.21"></a>
<FONT color="green">022</FONT>      // List for command line options.<a name="line.22"></a>
<FONT color="green">023</FONT>      private final List&lt;String&gt; options = new ArrayList&lt;String&gt;();<a name="line.23"></a>
<FONT color="green">024</FONT>      // List for command line parameters (arguments w/o options).<a name="line.24"></a>
<FONT color="green">025</FONT>      private final List&lt;String&gt; params = new ArrayList&lt;String&gt;();<a name="line.25"></a>
<FONT color="green">026</FONT>      // Log options.<a name="line.26"></a>
<FONT color="green">027</FONT>      private static final String[] LOG_OPTIONS = {"-verbose", "-v"};<a name="line.27"></a>
<FONT color="green">028</FONT>    <a name="line.28"></a>
<FONT color="green">029</FONT>      /**<a name="line.29"></a>
<FONT color="green">030</FONT>       * ErrorLogger default constructor.<a name="line.30"></a>
<FONT color="green">031</FONT>       */<a name="line.31"></a>
<FONT color="green">032</FONT>      public ErrorLogger() {<a name="line.32"></a>
<FONT color="green">033</FONT>        // Do nothing.<a name="line.33"></a>
<FONT color="green">034</FONT>      }<a name="line.34"></a>
<FONT color="green">035</FONT>    <a name="line.35"></a>
<FONT color="green">036</FONT>      /**<a name="line.36"></a>
<FONT color="green">037</FONT>       * ErrorLogger constructor which sets "args" given the argument.<a name="line.37"></a>
<FONT color="green">038</FONT>       * <a name="line.38"></a>
<FONT color="green">039</FONT>       * @param args The command line arguments<a name="line.39"></a>
<FONT color="green">040</FONT>       */<a name="line.40"></a>
<FONT color="green">041</FONT>      public ErrorLogger(String[] args) {<a name="line.41"></a>
<FONT color="green">042</FONT>        initialize(args);<a name="line.42"></a>
<FONT color="green">043</FONT>      }<a name="line.43"></a>
<FONT color="green">044</FONT>    <a name="line.44"></a>
<FONT color="green">045</FONT>      /**<a name="line.45"></a>
<FONT color="green">046</FONT>       * Initialize arguments and options.<a name="line.46"></a>
<FONT color="green">047</FONT>       * @param args String[] parameter passed from constructor.<a name="line.47"></a>
<FONT color="green">048</FONT>       */<a name="line.48"></a>
<FONT color="green">049</FONT>      private void initialize(String[] args) {<a name="line.49"></a>
<FONT color="green">050</FONT>        // Iterate through each args element.<a name="line.50"></a>
<FONT color="green">051</FONT>        for (String s : args) {<a name="line.51"></a>
<FONT color="green">052</FONT>          // Store argument to args list.<a name="line.52"></a>
<FONT color="green">053</FONT>          this.args.add(s);<a name="line.53"></a>
<FONT color="green">054</FONT>          // Check 's' is option?<a name="line.54"></a>
<FONT color="green">055</FONT>          if (isOption(s)) {<a name="line.55"></a>
<FONT color="green">056</FONT>            // Store 's' as a found option.<a name="line.56"></a>
<FONT color="green">057</FONT>            this.options.add(s);<a name="line.57"></a>
<FONT color="green">058</FONT>          }<a name="line.58"></a>
<FONT color="green">059</FONT>          else {<a name="line.59"></a>
<FONT color="green">060</FONT>            // Store 's' as a non option parameter.<a name="line.60"></a>
<FONT color="green">061</FONT>            this.params.add(s);<a name="line.61"></a>
<FONT color="green">062</FONT>          }<a name="line.62"></a>
<FONT color="green">063</FONT>        }<a name="line.63"></a>
<FONT color="green">064</FONT>      }<a name="line.64"></a>
<FONT color="green">065</FONT>    <a name="line.65"></a>
<FONT color="green">066</FONT>      /**<a name="line.66"></a>
<FONT color="green">067</FONT>       * Returns a boolean signifying the on/off of verbose option.<a name="line.67"></a>
<FONT color="green">068</FONT>       * @return Boolean of true/false.<a name="line.68"></a>
<FONT color="green">069</FONT>       * @throws NullPointerException in isVerbose.<a name="line.69"></a>
<FONT color="green">070</FONT>       */<a name="line.70"></a>
<FONT color="green">071</FONT>      public boolean isVerbose() throws NullPointerException {<a name="line.71"></a>
<FONT color="green">072</FONT>        String[] opts = getOptions();<a name="line.72"></a>
<FONT color="green">073</FONT>        // Check if options array has any elements or is null<a name="line.73"></a>
<FONT color="green">074</FONT>        if (opts == null) {<a name="line.74"></a>
<FONT color="green">075</FONT>          return false;<a name="line.75"></a>
<FONT color="green">076</FONT>        }<a name="line.76"></a>
<FONT color="green">077</FONT>        // Iterate through each option argument.<a name="line.77"></a>
<FONT color="green">078</FONT>        for (String op : opts) {<a name="line.78"></a>
<FONT color="green">079</FONT>          try {<a name="line.79"></a>
<FONT color="green">080</FONT>            if (op.equals(LOG_OPTIONS[0]) || op.equals(LOG_OPTIONS[1])) {<a name="line.80"></a>
<FONT color="green">081</FONT>              return true;<a name="line.81"></a>
<FONT color="green">082</FONT>            }<a name="line.82"></a>
<FONT color="green">083</FONT>          }<a name="line.83"></a>
<FONT color="green">084</FONT>          catch (NullPointerException n) {<a name="line.84"></a>
<FONT color="green">085</FONT>            return false;<a name="line.85"></a>
<FONT color="green">086</FONT>          }<a name="line.86"></a>
<FONT color="green">087</FONT>    <a name="line.87"></a>
<FONT color="green">088</FONT>        }<a name="line.88"></a>
<FONT color="green">089</FONT>        return false;<a name="line.89"></a>
<FONT color="green">090</FONT>      }<a name="line.90"></a>
<FONT color="green">091</FONT>    <a name="line.91"></a>
<FONT color="green">092</FONT>      /**<a name="line.92"></a>
<FONT color="green">093</FONT>       * Determines if a passed string is a valid option.<a name="line.93"></a>
<FONT color="green">094</FONT>       * <a name="line.94"></a>
<FONT color="green">095</FONT>       * @param str String to test option validity.<a name="line.95"></a>
<FONT color="green">096</FONT>       * @return The boolean value of true for option and false for not option. <a name="line.96"></a>
<FONT color="green">097</FONT>       */<a name="line.97"></a>
<FONT color="green">098</FONT>      private boolean isOption(String str) {<a name="line.98"></a>
<FONT color="green">099</FONT>        // Checks to see if contents of "str" is preceded by a hyphen '-'.<a name="line.99"></a>
<FONT color="green">100</FONT>        if (str.charAt(0) == '-') {<a name="line.100"></a>
<FONT color="green">101</FONT>          // Iterates through each option in "LOG_OPTIONS" array.<a name="line.101"></a>
<FONT color="green">102</FONT>          for (String op : LOG_OPTIONS) {<a name="line.102"></a>
<FONT color="green">103</FONT>            // Checks if "str" is a valid option.<a name="line.103"></a>
<FONT color="green">104</FONT>            if (str.equals(op)) {<a name="line.104"></a>
<FONT color="green">105</FONT>              return true;<a name="line.105"></a>
<FONT color="green">106</FONT>            }<a name="line.106"></a>
<FONT color="green">107</FONT>          }<a name="line.107"></a>
<FONT color="green">108</FONT>        }<a name="line.108"></a>
<FONT color="green">109</FONT>        // All else return nil object<a name="line.109"></a>
<FONT color="green">110</FONT>        return false;<a name="line.110"></a>
<FONT color="green">111</FONT>      }<a name="line.111"></a>
<FONT color="green">112</FONT>    <a name="line.112"></a>
<FONT color="green">113</FONT>      /**<a name="line.113"></a>
<FONT color="green">114</FONT>       * Returns the options determined from the argument list.<a name="line.114"></a>
<FONT color="green">115</FONT>       * @return String[] array of options.<a name="line.115"></a>
<FONT color="green">116</FONT>       */<a name="line.116"></a>
<FONT color="green">117</FONT>      public String[] getOptions() {<a name="line.117"></a>
<FONT color="green">118</FONT>        // Convert collection (List) to an array.<a name="line.118"></a>
<FONT color="green">119</FONT>        String[] optsArray = options.toArray(new String [options.size()]);<a name="line.119"></a>
<FONT color="green">120</FONT>        if (optsArray.length == 0) {<a name="line.120"></a>
<FONT color="green">121</FONT>          return null;<a name="line.121"></a>
<FONT color="green">122</FONT>        }<a name="line.122"></a>
<FONT color="green">123</FONT>        return optsArray;<a name="line.123"></a>
<FONT color="green">124</FONT>      }<a name="line.124"></a>
<FONT color="green">125</FONT>    <a name="line.125"></a>
<FONT color="green">126</FONT>      /**<a name="line.126"></a>
<FONT color="green">127</FONT>       * Returns the arguments passed into "args".<a name="line.127"></a>
<FONT color="green">128</FONT>       * @return String[] array of arguments.<a name="line.128"></a>
<FONT color="green">129</FONT>       */<a name="line.129"></a>
<FONT color="green">130</FONT>      public String[] getArgs() {<a name="line.130"></a>
<FONT color="green">131</FONT>        // Convert collection (List) to an array.<a name="line.131"></a>
<FONT color="green">132</FONT>        String[] argsArray = args.toArray(new String [args.size()]);<a name="line.132"></a>
<FONT color="green">133</FONT>        if (argsArray.length == 0) {<a name="line.133"></a>
<FONT color="green">134</FONT>          return null;<a name="line.134"></a>
<FONT color="green">135</FONT>        }<a name="line.135"></a>
<FONT color="green">136</FONT>        return argsArray;<a name="line.136"></a>
<FONT color="green">137</FONT>      }<a name="line.137"></a>
<FONT color="green">138</FONT>    <a name="line.138"></a>
<FONT color="green">139</FONT>      /**<a name="line.139"></a>
<FONT color="green">140</FONT>       * Returns the parameters of an argument list (params = args - options).<a name="line.140"></a>
<FONT color="green">141</FONT>       * @return String[] array of parameters.<a name="line.141"></a>
<FONT color="green">142</FONT>       */<a name="line.142"></a>
<FONT color="green">143</FONT>      public String[] getParams() {<a name="line.143"></a>
<FONT color="green">144</FONT>        // Convert argument list to array.<a name="line.144"></a>
<FONT color="green">145</FONT>        String[] paramsArray = params.toArray(new String [params.size()]);<a name="line.145"></a>
<FONT color="green">146</FONT>        // Returns null if arguments is empty.<a name="line.146"></a>
<FONT color="green">147</FONT>        if (paramsArray.length == 0) {<a name="line.147"></a>
<FONT color="green">148</FONT>          return null;<a name="line.148"></a>
<FONT color="green">149</FONT>        }<a name="line.149"></a>
<FONT color="green">150</FONT>        return paramsArray;<a name="line.150"></a>
<FONT color="green">151</FONT>      }<a name="line.151"></a>
<FONT color="green">152</FONT>    <a name="line.152"></a>
<FONT color="green">153</FONT>      /**<a name="line.153"></a>
<FONT color="green">154</FONT>       * Adds the error to be logged. Errors/Stack dumps are logged into a file under log/.<a name="line.154"></a>
<FONT color="green">155</FONT>       * @param er An Exception gets added to logger.<a name="line.155"></a>
<FONT color="green">156</FONT>       */<a name="line.156"></a>
<FONT color="green">157</FONT>      public void logError(Exception er) {<a name="line.157"></a>
<FONT color="green">158</FONT>        // Create file called "log".<a name="line.158"></a>
<FONT color="green">159</FONT>        File logDir;<a name="line.159"></a>
<FONT color="green">160</FONT>        // Create development.log file.<a name="line.160"></a>
<FONT color="green">161</FONT>        File devLog;<a name="line.161"></a>
<FONT color="green">162</FONT>        // File output stream object.<a name="line.162"></a>
<FONT color="green">163</FONT>        FileOutputStream out;<a name="line.163"></a>
<FONT color="green">164</FONT>        // Print stream object.<a name="line.164"></a>
<FONT color="green">165</FONT>        PrintStream ps;<a name="line.165"></a>
<FONT color="green">166</FONT>    <a name="line.166"></a>
<FONT color="green">167</FONT>        // Check if verbose option is on/off.<a name="line.167"></a>
<FONT color="green">168</FONT>        // Errors will only logged if "-verbose" option is passed as argument.<a name="line.168"></a>
<FONT color="green">169</FONT>        if (isVerbose()) {<a name="line.169"></a>
<FONT color="green">170</FONT>          // Create development log under log/ directory.<a name="line.170"></a>
<FONT color="green">171</FONT>          logDir = new File("log");<a name="line.171"></a>
<FONT color="green">172</FONT>          devLog = new File("log/development.log");<a name="line.172"></a>
<FONT color="green">173</FONT>          // Output file stream to file object.<a name="line.173"></a>
<FONT color="green">174</FONT>          // This will append to the existing "development.log" file.<a name="line.174"></a>
<FONT color="green">175</FONT>          try {<a name="line.175"></a>
<FONT color="green">176</FONT>            // Make directory called "log".<a name="line.176"></a>
<FONT color="green">177</FONT>            logDir.mkdir();<a name="line.177"></a>
<FONT color="green">178</FONT>            out = new FileOutputStream(devLog, true);<a name="line.178"></a>
<FONT color="green">179</FONT>            ps = new PrintStream(out);<a name="line.179"></a>
<FONT color="green">180</FONT>            // Output stack to screen. <a name="line.180"></a>
<FONT color="green">181</FONT>            System.err.println("**Error has been recorded in log/development.log");<a name="line.181"></a>
<FONT color="green">182</FONT>            er.printStackTrace();<a name="line.182"></a>
<FONT color="green">183</FONT>            // Write stack dump to file.<a name="line.183"></a>
<FONT color="green">184</FONT>            er.printStackTrace(ps);<a name="line.184"></a>
<FONT color="green">185</FONT>            try {<a name="line.185"></a>
<FONT color="green">186</FONT>              out.close();<a name="line.186"></a>
<FONT color="green">187</FONT>            }<a name="line.187"></a>
<FONT color="green">188</FONT>            catch (IOException io) {<a name="line.188"></a>
<FONT color="green">189</FONT>              System.err.println("IOException.");<a name="line.189"></a>
<FONT color="green">190</FONT>            }<a name="line.190"></a>
<FONT color="green">191</FONT>          }<a name="line.191"></a>
<FONT color="green">192</FONT>          catch (FileNotFoundException fnf) {<a name="line.192"></a>
<FONT color="green">193</FONT>            System.err.println("FileNotFound Exception.");<a name="line.193"></a>
<FONT color="green">194</FONT>          }<a name="line.194"></a>
<FONT color="green">195</FONT>        }<a name="line.195"></a>
<FONT color="green">196</FONT>      }<a name="line.196"></a>
<FONT color="green">197</FONT>    }<a name="line.197"></a>




























































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